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- Use that "ebay" adapter instead of the stock fuel pressure regulator.
- Flop the two rubber hose steel line connectors by the driver's side after the driver's fuel rail
- Run a fuel hose from the "ebay" adapter outlet to the fuel vapor conduit inlet.
-Run a separate goodyear hose to connect the fuel vapors, paralel to the fuel vapor conduit.
-Use a brass T connector to tee together by the factory fuel line in and out ports.
-Install a stand alone fuel pressure regulator by the factory vapor steel line, pick-ul vacuum by extending the vacuum hose from the factory location.

Basically, This above arrangement extends "artificially" the driver's fuel rail "loop", to make it closer in overall length to the passenger side.
It uses the fuel pressure replacement adaptor as a T, then takes the merged return flows back through the vapor conduit and has a fuel pressure regulator in an area under the hood where there's room for it (roughly close to the underhood fuel filter, for a 2002 wrx).
The fuel vapors, under my opinion can be transported through a rubber pipe more easily, less potential headaches there.

The possible downside is that the vapor steel line may be of a smaller diameter, but the regulator may adjust that.

I'm not sure, I'd have to look at my initial design again first and follow the lines. IMHO, the length of the line does not matter as it is all pressurized. Basically all I did was swap the return and feed on one side and T the inputs/outputs (before the stock rails where they attach) so I could keep the stock bottom hard lines (I don't want anything to kink and blow a piston). You could do this with the mani on as well.

I just needed one adapter though and the fuel line fits right on the stock FPR fat end like on the scoobymods tutorial. I ended up using less than 2 feet of goodyear fuel injection hose.

Gabe

EDIT: The length of the line after the Ts does matter, see my posts below

Last edited by gabedude; 06-14-2009 at 11:39 AM.
Reason: Good idea at first but in practice it causes some issues

I am modding mine today... I dont even have to take my manifold off or anything I bought two brass tees some FI clamps and couple feet of FI line. I am doing it basically the way gabedude did it because I want to keep the hard bottom lines too I could only imagine doing this mod and then one line getting pinched or something stupid ...My total cost was $22 , keep in mind I have an aftermarket FPR already so thats all I needed...

Well I was going to try and explain how "I" did it but a picture is worth 1000 words...

I disconected stock feed and return lines...

Since I Ripped my A/C out and it was very easy to get to, I used these for my passenger rail feed and my drivers side rail return... anyone could probably easily use them if you took the manifold off...

Then I just set up my lines...

I used the stock fuel rail feed as the feed for the driver side rail and I used the stock return line as the passenger side rail return...

I'm not sure, I'd have to look at my initial design again first and follow the lines. IMHO, the length of the line does not matter as it is all pressurized. Basically all I did was swap the return and feed on one side and T the inputs/outputs (before the stock rails where they attach) so I could keep the stock bottom hard lines (I don't want anything to kink and blow a piston). You could do this with the mani on as well.

I just needed one adapter though and the fuel line fits right on the stock FPR fat end like on the scoobymods tutorial. I ended up using less than 2 feet of goodyear fuel injection hose.

Gabe

gabe - would you recommend the goodyear hose? i forgot what i bought (i think i picked my fuel line up from advance auto) but i keep getting small leaks and its driving me insane. it only does it when the car starts up but its annoying as hell to keep having to pull them mani off and tighten down the clamps and i still seem to have a problem. i used loctite as well. i havent noticed a smell in a few days after tightening and using loctite but i just dont want to have to deal with this crap again

i took out the stock hard lines, just the rubber lines. everything is under the mani and free of any kind of kinks or anything of the like.

When you took out the stock hard lines, what did you use to connect the fuel rails and the hose? Are the barbed fittings that will screw in to the rails?

I haven't taken mine apart yet, but I'm building a shopping list... I want to remove the hard lines while I do this, to make more room for the pipe that runs from my FMIC to my throttle body (Legacy GT).

Just an update. Make sure to use equal length line after the T-s if you do this. I reused the stock hard lines and ended up going lean on one bank and rich on the other causing high EGT spikes and rising coolant temps during throttle transition. So to do it right, make sure your feed and return lines going to each rail are equal length (which means do not re-use any of the stock hardlines). I would recommend not using soft line either, use -6 AN lines if you can or just the steel braided hose and bard fittings.

I don't want to remove the manifold again, so I am just buying rails (the new design of the AP rails which are much like TXS rails).

yeah if you use braided hose, you are going to need to flare the stock line. i was going to do this but decided last minute to just keep it as is. i dont have any hardline (other than the hardline rails).

I thought it was a good idea, but it is actually a bad idea (your pics are exactly what I did). I don't think it would cause a motor to pop right away, but on throttle transitions, one bank is gonna go lean and the other rich causing a short EGT spike. Keep on driving and your coolant temps just rise and rise. It is very noticeable in the Texas heat here, especially with ym front mount and the stock radiator. My coolant temps got up to 220 or so max and I didn't like that. The EGT spikes are short, but over time it would probably cause damage.

You don't ever really need them according to most tuners. However it is of my opinion that when changing from stock injectors, you should use them because the OE fueling mapping has compensations in them per cylinder for the series configuration. Once you change injectors, your fueling will not be as close as the factory fuel setup and each cylinder will be even more offset in the true AFRs they are running. Ideally you would want a WBO2 in every cylinder and a knock sensor or more advanced device + the logic to control it. However, that gets very expensive. Old WW2 planes used an FPR and equal length lines on every cylinder. They tuned the engine with a knob to lean out the fuel and watched the temperature sensors in the heads of the turborcharged engine. We gave lamba sensors these days and EGT sensors.

So if you change injectors at least I think it is a good idea to run a true parallel configuration, 0 out those tables (perhaps add in a tad extra for the second injector in each bank nearest the return line). Also, your knock sensor is over #4 and there is a table that adds in extra timing over 4 to detect the onset of knock. that is why 4 goes out the most because it takes the brunt of detecting knock. It is not that 4 gets starved of fuel. 4 gets fuel before the other bank does.

I was going to switch to parallel fuel routing when I upgraded my turbo inlet, since the manifold had to come off anyway, but decided to wait until I can measure the results. I think I'm going to get four of the PLX units next spring. I'm going to get new headers, so I'll be messing around with the part of the car anyway, and I can have the bungs welded in before they go on.... maybe.

I was going to switch to parallel fuel routing when I upgraded my turbo inlet, since the manifold had to come off anyway, but decided to wait until I can measure the results. I think I'm going to get four of the PLX units next spring. I'm going to get new headers, so I'll be messing around with the part of the car anyway, and I can have the bungs welded in before they go on.... maybe.

I'm getting the APS header system pretty soon (already paid for it) and it has the 4 1/8npt ports already on it. I would be interested in renting it off of you at some point when I switch up fueling. I figure I'll need to sooner or later, E85 is going to overtax my current fuel system I'm pretty sure.